Hyare Harpreet, Wisco Jonathan J, Alusi Ghassen, Cohen Marc, Nabili Vishad, Abemayor Elliot, Kirsch Claudia F E
Department of Neuroradiology, Barts and the London NHS Trust, London, UK.
Surg Radiol Anat. 2010 Dec;32(10):937-44. doi: 10.1007/s00276-010-0638-0. Epub 2010 Feb 24.
To analyze, from 1.5 Tesla (T) MRI clinical cases, anatomical accessibility of nasopharyngeal tumors through the pharyngobasilar fascia (PBF) to the mandibular nerve for potential perineural spread.
A 6-year retrospective review of 1.5 T MR images were rated for tumor involvement of fascial planes and perineural spread in 15 consecutive patients (10 female, 5 male; mean age 45.8 years, range 19-86) with histopathologically proven tumors of the nasopharynx and referrals for radiotherapy due to intracranial extension.
Nasopharyngeal tumors were best appreciated on T1 fat-saturated, post-gadolinium MRI. Tumors extended through the sinus of Morgagni in all cases. This sinus is a defect in the PBF through which the Eustachian tube and levator veli palatini muscle gain access to the nasopharynx. In six patients, the PBF and tensor veli palatini fascia were breached anteriorly with tumor infiltration of the tensor veli palatini and medial pterygoid muscles. In 13 cases, tumor breached the posterolateral PBF with extension into the poststyloid parapharyngeal space. In three subjects, 3 T images were also acquired and exhibited superior delineation of the anatomy and perineural tumor spread.
At 1.5 T, images showed nasopharyngeal tumors extending through the PBF into the masticator and parapharyngeal spaces, with access to the mandibular nerve and potential for perineural spread. At 3 T, soft tissue resolution appeared superior to 1.5 T. This may reflect not only the increased field strength, but an improved technique and matrix, and future studies are necessary to confirm this observation. Awareness of this anatomy for radiation and surgical planning is essential and may improve the ability for obtaining negative margins, and increasing overall survival.
通过分析1.5特斯拉（T）的MRI临床病例，研究鼻咽肿瘤经咽颅底筋膜（PBF）至下颌神经的解剖可达性，以探讨其潜在的神经周围扩散情况。
对15例连续患者（10例女性，5例男性；平均年龄45.8岁，范围19 - 86岁）进行了为期6年的回顾性研究，这些患者均经组织病理学证实患有鼻咽癌且因颅内扩展而转诊接受放疗，对其1.5T MR图像进行筋膜平面肿瘤累及情况及神经周围扩散的评估。
在T1脂肪抑制增强MRI上，鼻咽肿瘤显示最佳。所有病例中肿瘤均通过莫尔加尼窦扩展。该窦是咽颅底筋膜中的一个缺损，咽鼓管和腭帆提肌通过此缺损进入鼻咽。6例患者中，咽颅底筋膜和腭帆张肌筋膜前部被破坏，腭帆张肌和翼内肌有肿瘤浸润。13例中，肿瘤突破咽颅底筋膜后外侧，延伸至茎突后咽旁间隙。3例患者还获取了3T图像，其对解剖结构和神经周围肿瘤扩散的显示更清晰。
在1.5T时，图像显示鼻咽肿瘤经咽颅底筋膜延伸至咀嚼肌和咽旁间隙，可累及下颌神经并有神经周围扩散的可能。在3T时，软组织分辨率似乎优于1.5T。这可能不仅反映了场强的增加，还反映了技术和矩阵的改进，未来研究有必要证实这一观察结果。了解这一解剖结构对于放疗和手术规划至关重要，可能有助于提高获得阴性切缘的能力并提高总体生存率。
